Automatic telephone-exchange



I F. A. LUNDQUIST. AUTOMATIC TELEPHONE EXCHANGE.

APPLICATION FILED AUG.2I, I900- 1369,2863. I Patented Feb. 22,1921.

-QsHEETS-SHEET l- WWM- ' F. A QLUNDQUIST. AUTOMATIC TELEPHONE EXC HANGE.

APPLICATION FILED AUGJI. 1900.

. Patented Feb. 22,1921.

10 SHEETS SHEET 2.

v F. A. LUNDQUIST AUTOMATIC TELEPHONE EXCHANGE. APPLICATION FILED Aue.21. 1900.

Patented Feb; 22,1921.

9 SHEETS-SHEET 3.

F LUNDQUIST. AUTOMATIC TELEQHONE EXCHANGE. A PPLlpATloN FILED AUG-2|, 1900.

1,369,288; Patented Feb. 22,1921.

0 S.HEETSSHEET 4.

F. A. LU NDQU|ST. AUTOMATIC TELEPHONE EXCHANGE.

APPLICATION FILED AUG;2I, 1900.

1,369,288. Patented Feb. 22,1921.

1o SHEETS-SHEET s.

INVENTOR W/TNESSES I v I BY vF. A. LUNDQUIST.

I AUTOMATIC TELEPHONE EXCHANGE.

APPLICATION FILED AUG-2|. 1900- '1 369,8. Patented Feb.22,19211.-

10 SHEETSSHEET 6- IA/HA/ESSES.R V A: V r a Y OR I I BY I 'a..ba; zm

F. A. LUN DQUIS-T.

AUTOMATIC TELEPHONE EXCHANGE.

APPLICATION FILED AUG.21, 1900.

1,369,288. Patented Feb. 22, 1921.

10 SHEETS-SHEET 7.

00 on so 090 one 0 can -ooe e /N VENTOR ATTORNEY F. A. LUNDQUIST. AUTOMATIC IELEPHONE EXCHANGE.- APPLICATION FILED Aua.21, 1900.

1,369,288; I Pa en e Feb. 22, 1921.

10 SHEETSSHEET 8.

- lfiwwkwaw I [huenTor F. A. LUNDQUIST.

AUTOMATIC TELEPHONE EXCHANGE. APPLICATION FILED Auc.2l, 1900.

1369288. Patented Feb..22, 1921.

I0 SHEETSSHEET 9.

JMQW s WAM F.'A. LUNDQUIST.

AUTOMATIC TELEPHONE EXCHANGE.

APPLICATION FILED AUG-ZI, I900.

Patented Feb.22,1921.

' Fig.

WiIrzesses:-

uNi' r Eo STATES PAT NT,mice-j;

FRANK A. IiUNDQUIST, CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO WESTERN ELECTR 'IC COMPANY, Y INCORPORATED, A CORPORATION NEW YORK.

AUTOMATIC TELEPHONE-EXCHANGE.

Patented Feb. 22, 19 21.

Application filed August 21, 1900. Serial. No. 27,549.

To all whom it concern:

Be it known that LFnANK A. LUNDQUIST, v

a citizen-of the United States of America, and a resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Automatic Telephone-Exchanges, of which the followin is a specification. r I

Fly invention relates toautomatic :tele: phone exchanges. The principal feature of this invention resides in the provision of means whereby when two switches make connection to the same line, the talking conductors to the brushes of the switch-last to make connection to the line will "be inter.- rupted. 1'

In. the present application.- the central otficeapparatusfof a telephone exchange is I arranged with its devices in two groups respectively called main switches and auxiliary switches. The, mam switches and auxiliary switches are substantially the same in constructlon andoperat1on,- the differences between the two bemg pr1nc1-.'.

pally in the electrical connections made by them rather than in struction. 1 .7

Inthe accompanying drawings Figure l is a front elevation of a. mainswitch and corresponds to Fig. 4, which isa front elevation of the same switch used as an auxiliary switch; Fig. 2 is a rear elevation of an auxiliary switch; Fig. 3 is a side'elevation of an auxiliary switch; Fig. 5' is a, detail in plan showing part of the switch as it would be on either the main or auxiliary switches;

Fig. 6 is a detail inside elevation, partlyin section, showing some of the operating parts asarranged on an auxiliary switch; Fig.7

is a plan of the switch carriage-detached; Fig. 8 is a section on line 88 of Fig. '7

Figs. 9and 1O are'details; Fig. 11-is a.

general diagram showing the'electrical connections betweentwomain switches andone auxiliary switch, with a detached portion of a second auxiliary sWltCli't0' 'Sl10W the manner in which the non-interfering device is: operated and Figsx-lQ, and 14 taken toa bracket G on the carnage- G is aholding the operation and con-' gether form an abridged diagram showing the arrangements for interconnectingthe non-interfering devices in exchanges of the kind illustrated in my Patent No. 776,524, issued-Dec. 6,1904.

Briefly stated, a switch consists of some contact points and contactv makerstherefor, a magnet A. for moving the contact makers in one direction, a 1 second magnet B. for moving them in a direction perpendicular to the first movement, and certainother magnets, C. D. and E. for makingand breaking electrical connections as will be hereinafter described In the said drawings F. is a vertical frame on which is secured-a piece of insulation F in which-insulation are a series of contact points F Secured on-the face of the frame F are three posts F which serveas guides for aFcarriage G, which carriage, is made up of two parallel barsgG and a third bar parallel to the other two,.but located below and between them. These side bars are connected together by cross-bars G and onthe bar G is mounted a second carriage H'. On the carriage H is aipiece of invsulation H (Fig.7.) which, in the main switch, carries two contact makers P and P and in the auxiliary switch'carries three con-- tact makers,"which "fior convenience have been marked P P and P". On the bar G of the'first carriage is a ratchet rack G having-teeth facing in two directions, andthe carriage H is asimilar'ratchet rackwith' teeth facing in two directions. Onthe back of the frame F is secured a magnet A on the armature lever A of which'is a pawl-A adaptedto engage the ratchet G so as to movethe carriage upward in its guides F Supported ona post A is a pawl A which engages the ratchet G so as to hold it inthe position into which it has been moved by the operation of magnet A. Also on the back of the frame F is a magnet B whose armature lever B carries a pawl B adapted to engage the ratchet teeth of the carriage and move said carriage transversely to the movement of thefirst mentioned'carriage- Secured to oftheaction of these two ma nets is to move t .W ll beobservedfrom thisdescription tha j h ..magnet. A, moves the arnage up-t ward the required distance and that the magnet B moves the second carriage. trans? versely any required distance. The resultthe contact makers'P and B of the main switch, 'or P P and P of the auxiliary 5' switch, over the rectangularly arranged contact pointsFZ. r I

Supported ont'he frame F-is a po'stJ to which is'pivot'ed a lever J normally held by a spring'in contact with the post J. 1 Piv= oted to the lever J is another lever J which projects toward the middle of the machine and over the armature lever A as is shown 'in'Fig. 9., Between the endsof the lever J is-a hook which lies'adjacentto a tail piecev A on the holding' p awl A. If the leve'rd be moved to the left from the position-as S WIl in Fig. 9, the hook on thelever'J willen'gage the tail iece A on the pawl-A2 when, if the lever be then permitted "to move'to the right against the stop pin J the-said :hookfwill draw the pawl A out of engagement with the ratchet G thereby-releasing it and permitting the carriage to drop to its lowest position, which lowest position is determined by the post F and aset SCIGVF", against which thebar G strikes.

" On'the carriage'H-isa 'sprin VH one end of which is attached to a pin 5 in the carriage H, and the otherend of which is "at tachedto a pinH securedto the right hand side bar G of the main carriage. The s ring H is arranged to draw the" carriage to' the right to its extreme or normal position when relea'sedfrom itsholding pawl H The position of the spring H is'such that its action is directly in line with the travelof the carriage H, so that in: drawing it back to its normal position there is practicallyno lateral strain to-produce frictional-re; sistance. In the same way the main "car-- riage, by movingdirectly upward and-beingguided in easily fittingguidesin posts F is; when, released, entirely freefrom lateral; strain. By arranging these ;two'carr1ages so that when-they are released ;-they are freeto' move independently. of" any-Z outside strains,-'I am enabled to make-the propelling mechanismlighter than would: otherwise be, the case. gngthe, lower right hand part: of the switch; as, shown in Figs? 1'- and 1 1-, there? is' a -mag net D' whose armaturelever D? is.

i 1 arrangedsto make certain electrical. 'conne'c-v tionfs; ithe -ma' in' switch this magnet makes only one such electrical connection,

armature *lever 1 13.

whilein the auxiliary switch it makes two electrical connections and breaks a third. On the armature lever D of the switch used as a main switch, there is a second lever D witha 'pifiJ seeured to a' lever which last lever is also pivoted to the lever J $1 9+ ufi i envl 9i the-.le eP-J? is provided .withra hook which isadapted to engage a pin B which 'projcts from the side of the In its normal position the lever J* is not in the path of the pin B when theinagnet B operates to move thecarria'ge'H to the left. If, however, the magnet' Dshould-beenergized at the same time the magnet B is energized,'then the projecting arm D will pujsh thep'in'J so as to raise the "levenJ into' the path "of the pin B? ,-so that the action 0f the magnet 'B' willbe to pu'sh the lever J' 'to the left and cause the hook thereon'to release" the pawl A as has been previo1'i"sly" des'cribed The same {result would occi'1r it-thearmature 'lever A be moved upward immediately beforethe magnet B operates" a d is then released before themagnet"B is "-demagnetized. 'This'will be observed jfroin Fig; 9"as' it will be seen that the movement" upward of'r' the armature A pushes the levers J and J into the path of the'pin B, when upon-the release-of the lever 'A the lever J will drop into enga e ment with the tail piece A on the pawl r- It will, thereforeybel; apparent'tha't'thea cti'on-of the magnetrk and' magnet B together," 'or"the 'action of" magnet D and" ma net B "together, will result inafeleasing the pawl A and" permitting the carriage to drop toits lowest 'position". I The instant the'carriage reachesfiits lowest p'oint the'tail piece H on'the 'pawl H strikes' the pin J and releasesthercarri'age H, whiehis" then retracted by theispring =H f Atth'e left front side of the main switch a'magnet'C which is arranged tomove contact maker 23 from the'contact 24' to a contact 535 Supported adjacent 'to the magnet Q is a pivoted lever C -.which is engaged shyi5l1epin-Gr on the bar G when'the 'm'ain carriage is at its lowest position; 1 The armature lever G which carries th'e contact'maker 23', projects adjacent to the lever T (1 but is not engaged bys'aid' lever "when the lever is engagedbymoved upward so I toleave1the 'lever "C free, then''lf the "magnet .C' be energized, the;

armature'leverI' G he caught" by: hook on the end ofthe -lever C nthereby: holding the contact :rnaker 23Lfaway from the 'contactiQ lQ andaintof:engagement 'ivitlrfithe -contact 53.

On: :the abackof; ithe auxiliary switch as I 7 shown in figs? 3 ==and 6, Zthere l'i's supported lever is" provided J'with' hook which lies 'ad' jacent to a hook A on the armature lever provided with 3 an armature Thefen'd"of t-hefarmaturelever E v Aofthe magnet A. These parts are so 811",

ranged that if the magnets A and E operate simultaneously, then the hook E will be caught bythe hook A? and be held with the armature lever E out of engagement with two contact points '43; and 79 as shown in the upper p'artof the diagram Fi 11. The operation of the parts I51 and 3 will be more readily understood by the inspection of said diagram than by the parts themselves-as shown in Fig; 2. I The difierence between the contacts made by the magnets on the main switches and those made by the magnets on the auxiliary switches may also be'best seen by inspection of'Fig; 11. Thus, the armature lever A of a main switch, whenmoved by its magnet A, opens the electrical connection at a spring 30, and closes connections between contacts 36 and 37, '50 and 51, and 95' and 96 The samemovement on an auxiliary switch operates in a" similar way similar contacts, for example, it opens connection to contact point 45, closes connection -between contacts 81 and 82, and shifts the contact spring 89 from connection with contact point 91 to connection with contact point 88. In the main switch the magnet D closes one contact while in the auxiliary switch it closes two contacts and opens a third.

In arranging a telephone exchange I place the central'office devices in the manner which is illustrated" in -my Patent No. 776,524, issued December 6, 1904, to which reference may be had for an illustration of the general principles of grouping main and auxiliary switches. Briefly described that manner is as follows I place a-large number of main switches in arow, or in any convenientmanner, and these I divide 'into comparatively large groups depending upon the numbe'r of contact points arranged in the auxiliary switches. In this case there would be sixty such main switches in a group; and for each group ofmain switchesT provide a smaller group of ten auxiliary switches.

switch represents, or are connected to, the different auxiliary switches of the first group: the second row of contact points are similarly connected. to the second group,.and

so on. In the auxiliary switches the contact The first a vertical row of contact points on a main the connected main-"switchup one step. He

then closesthe second contact point a required number of times, which results; in moving "the carriage Hand, consequently the pointers P and P laterally to are quired vertical row of contact points. He then closes'the first contact ten successive times to move the carriage upward. The

connections are soarranged that when the pointers P and P reach aconnection to an auxiliary switch which is not employed, the

connection to'the'moving magnet is broken and the unemployed auxiliary switch is automatically moved from its position so that it can notbe reached by any other main switch and is, consequently, transferred from the unemployed to the employed class, He then closes the second contact-which moves the auxiliary switch upward one step. Hethen'cl'oses the first contact point the required number of times which results in moving the carriage H of his auxiliary switch laterally to the required vertical row oi": contact point.' He then closes the-second contact a required number of times, which moves the pointers P? and P upward to the required or selected. contact points which are connected with the required switch 0 the telephone which 'is-to be called Taking these operations in detail, when the calling subscriber closes the first contact point once, acurrent flows asefollows:

Battery X-'20telephone station'21 This moves the carriagelof-his switch up ward one step and brings the ratchet on the carriage in line with the pawlB which contact only once. Glosing'the' second'con tact sends acurrent as follows "X10020" teie'phone station-28-293 0'A ca rriage 31-z32 33 B27+ 99X. This moves the carriage laterallyand is repeated the required numberiof times to bring the" and P to the required verticalpointers "7? rows; Closing the first contact'ten-times re the pointers; P and P reach contact points which are'connected to an auxiliary switch which is not in use when, by reason ofcon tact made between 36 and 37 at each opera"- tion of the magnet A. a current'flows as follows :1 Wi -34+35 se a7 0-439-- 40 P 41 42-E 4344 45 A of the auxiliary switch carriage'46-47"=D-* 4849--'Y. Thejcurrent through C of the "I20 sults in moving the carriage upward until i of the others were in use. If, h0wever, the first, is employed by someother main switch,

' at the first one unemployed.

main switch breaks the circuitfor the magnet A at 23+24, thereby automatically stoppingthe carriage of the main switch, in

conn ction. with the first auxiliary switchfound ,unemployed. It therefore follows that all of the ten contacts made, more than enough to connect to the idle auxiliary switch, are not effective. The reason for making ten contacts is that, as previously stated, -the ten contact pointsin a vertical row are'connected to the ten auxiliary switches constituting one group, and, as an undetermined number of these are normally-in use, it is necessary to1move the I niamswitch far enough to reach one that is unemployed. If it so happen that none is employed when the main switch is moved, then- -tl1emoved main switch will automatica-lly 1-st-0p at the first contact point. The same result would happen if the first auxiliary switch. was unemployed while several then the moved main switch will pass over the'contac't point connected to thefirst auxiliary switch and be automatically stopped As it may frequently happen that the first nine aux- VmagnetflD'of this auxiliary switch.

iliary switches are employed while the tenth isynot, fit is therefore desirable to always make ten contacts so asto be sure to reach an unemployed switch. Besides, as the calling subscriber is'not at the central office and has no' means of knowing what auxiliary switches are employed and what unemployed, his only practical method of being sure to reach one of the ten is to make con- V tacts-enough to reach the last of the seriesin caseall of the others are in use. T 0 prevent the break at 2324 from releasing magnet A before the second operations are completed, there is a shunt from 21 to 25 by way of'50-5152, which is closed by themagnet A'and which holds the current through itself until the circuit is broken at V the telephone. Breaking connection at 23 24 closes it between 23 and 53, and as this occurs after the carriage has been moved up, the catch C is free to catch the armature lever C and hold the connection between 23and 53 to be used in the next contact made at the telephone. The current through Diof the auxiliary switch closes 55 and 56 when a current flows as follows: X--100 switch 59 6O 99 The current throughAof the auxiliary switch moves its carriage-up one step breaking the connection betweenthe carriage and the contact 46, thus preventing" some other switch from connecting its magnet C in, series with the This action, therefore, removes the auxiliary switch from the class ofthe unemployed to the class of the employed switches. To

prevent the bre k-between -;the carriage and a6 from releasing magnet Dytoo soon, there is a shun-t frontal to 47 byway of .6l"-62:i.' 63,"which "is closed by the magnet 1),; and which holds the current through itself until the line is broken 'at 36;.37 bythe releasing of the magnet A of. the mainis witch. Then closing the second contact a current flows: X'l0O, 20'telephone station. 28- 29- -30 contact point 58 A of the; auxiliary auxiliary carriage upward to; connection with the contact 93, Then closing the first contact a current flows I X- 10020telethe required row. Then closing-thesecond 5323- 22-2l callingtelephone station. To release, both the first and the second contacts I close simultaneously,when a current flows- X100-te1ephone' 'st'atione 28 29 30 A ca'rriage'61-D-62-- P58A of the auxiliary switch59-60 99X. D closes D to 80 and A of auxiliaiv switch closes 81 to 82. .When a cur-' rent flows X100 +20-telephone -station n This operates D and B of the main switch,

and A and B of the auxiliar'yswitch, which as previously described, releases the holding pawls of both switches and permits the carriages to drop back to their normal posh tions. V a 1 ,For convenience in arranging-the switches and connecting them together there are banks of wires like 71 and 76, at theupper part of Fig. 11, which connect thecontact points belonging-to the pointers P and'P and from these wires, branches, 72 and 75, extend to the normal contact points of the different main switches. Thisarranga ment of banks of: wires and their branch, connections'issimilar to that shown in my previously 'mentioned 'Patent No. 776,524, andyalso, similar; in a general sense towell known connections. In addition to these wires just described, there is an additional the auxiliary switches which are appropri-- ated to the pointerl,oforiexamplez The wire 84: would have branches, S3, to a corresponding contact point on each and every auxiliary switch in the exchange when there is only one group of auxiliary switches as shown in Fig. 11. When there are a plurality of groups, as shown in my before mentioned patent, then there is a separate set or bank ofthese wires 84 for each group of auxiliary switches. Other wires belonging to this bank would have corresponding branches to their contact points on the auxiliary switches. At the right hand upper portion of Fig. 11 there is a detached portion of a second auxiliary switch which corresponds to the portions similarly marked in the auxiliary switch which is provided with a complete diagram. There is provided a battery Z which is connected to all of the magnets E of the auxiliary switches in the manner which is shown. If while the auxiliary switch which we have been previously describing as having made the connection between two main switches is on the points connected to the bank wires 7176 and 84, a second auxiliary switch moves its pointer P to a contact point corresponding to the same bank wire 84, then a current from the battery Z will flow as follows: Z 8586E of the auxiliary switch which has last moved to this connection-8788 89-(magnet A of the second auxiliary switch being in the act of moving to the designated l point)-90-P--83-8%83 of the auxiliary switch which first moved to the operating connection, P-90--8991- 92-Z. This energizes magnet E of the auxiliary switch last moved to the connection and as this occurs while A is attracted then upon the release of both magnets A and E-E will be caught by the hook on A and E will be held from 79 as shown at the right upper hand part of the diagram. As the talking circuit passes through 79 of the selected auxiliary switch, it will be evident that the talking circuit is broken when the auxiliary switch moves to a connection which is previously occupied. The magnet E and its connections, therefore, constitute a non-interfering device which does not prevent the auxiliary switch from being moved to any position, but does prevent a moving auxiliary switch from interfering with any talking circuit that has pre viously been made.

In tracing this non-interfering circuit through the condensed diagram any one of the auxiliary switches in the upper part of Figs. 12 and 13 may be assumed to be the first in connection with a called station, and either of the othersthe second or interferingswitch I I. 1 N

.T he auxiliary switchhof Fig. 14,- being interconnected: in a separate group of auxiliary switches, does not operate through-any oi'. the connections made by those; .of Figs. 12 and 13.

What I claim is 1. In a telephone system, an exchange, subscribers lines terminatingthereat, pairs of talking conductors at said exchange, switches for respectively connecting said pairs of conductors to any desired line, a circuit breaking device at each switch, and an electromagnet operated upon two switches makingconnection to the same line to cause said circuit breaking device to interrupt the conductors of the last connected pair.

2. In a telephone exchange system, telephone lines, pairs of talking conductors, switches having brushes 'for extending said pairs of conductors respectively, multiple terminals of said lines arranged to be traversed by the brushes of said switches, a circuit controllingdevice at each switch, and means for operating said controlling device when a second switch engages the contacts of a line to interrupt the pair of conductors terminating in said switch.

3. In a telephone system, subscribers lines, connector switches, multiple terminals of said lines at said switches, selector switches, talking conductors terminating at said connector switches respectively, multiple terminals of said conductors at said selectors, means for automatically operating a selector switch to pick a conductor terminat-v ing at an idle connector switch, a circuit controlhng device at each switch, and an electromagnet operated when a second switch unites with one of said lines to cause the circuit controlling device of the second switch to interrupt the conductors leadin from a selector to said switch.

4. In a telephone system, a pair of metallic circuit subscribers lines leading to a central oflice, selecting switches at said central oflice, trunk lines controlled by said selecting switches for connecting. said pair of lines together, a pair of controlling magnets at each of said selecting switches simulta-, neously bridged across the talking circuit between said, two stations, a source of current adapted to supply current to the limbs of said line through said magnets, and means at one of the subscribers stations for-c108 ingthe circuit through said magnets for the operation of said switches, substantially as described. a

5. In a telephone system, a metallic talking circuit extending in two limbsfrom a central station to a substation, a plurality of selecting switches at the central station forextending the limbs of said talking circuit, a source of current at the central station, a, controlling magnet for each of said magnet for each of said selecting switches connected between the other limb of said talking circuit and the same terminal of said source, and a return path for the other termina1 of said source. I 10 Signed at Chicago, 111., this 25th day of July 1900. e

V FRANK A. LUNDQUIST.

Witnesses:

LOUISE PETERSEN, CASPER L. REDFIELD. 

